Nitrogen limiting factors

Nutrients—Nutrients, such as nitrogen and phosphorus and other trace elements, are necessary for cell growth because they are key biological building blocks.52,53 Addition of nutrients as a supplement helps ensure that concentrations of nutrients do not become a limiting factor for bioremediation. 

Enhanced biorestoration is a means by which naturally occurring processes are deliberately manipulated to increase or enhance the rate of cleanup. Biological activity in the subsurface is controlled by the availability of one or more of the necessary metabolic requirements such as an electron acceptor or nutrient. Although electron acceptors are most often the limiting factor, inadequate availability of nitrogen, phosphorus, or micronutrients (such as potassium, copper, or even vitamins) can restrict optimum restoration. When the proper balance of these factors is established, the rate of chemical degradation is maximized. 

The process of nitrogen fixation is an essential part of the nitrogen cycle on the planet earth(l). It is estimated that greater than 60Z of the N2 that is ultimately converted to NH4+ is done so by the nitrogenase enzyme system. The availability of fixed nitrogen is often the limiting factor in plant growth( ). To... 

Rate-limiting factors for bioremediation can include a lack of sufficient organisms with the metabolic pathways required for degradation. Temperature, oxygen supply, contaminant availability, chemical structure of the contaminant, and soil chemistry can all effect aerobic biodegradation rates. Nutrients such as nitrogen and phosphorous are necessary for biodegradation. 

Acetaldehyde Oxidation. In the oxidation of acetaldehyde with oxygen-nitrogen mixtures, at conditions under which the rate-limiting factor is oxygen transfer to the solution, manganese (II) acetate gives a better efficiency to acetic acid than copper (II) acetate, which in turn is better than cobalt (II) acetate. However, when either cobalt (II) or copper (II) acetate is used in the presence of manganese (II) acetate, the... 

Application of LIDAR techniques to the measurement of nitrogen species has been very limited. Sensitivity seems to be the limiting factor. For N02 a detection limit of about 100 ppbv in the lower troposphere is reported for a resolution of 50 m along the laser path (16). 

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